Control system



Sept. 17, 1929. HIG-BEE 1,728,759

CONTROL SYSTEM Filed Sept. 30, 1927 2 Sheets-Sheet 1 Fig. I. L

7 INVENTOR Ray EH i g bee Y 2 7 ATTORNEY p 17, 1929- R. P. HIGBEE 1,728,759

CONTROL SYSTEM Filed Sept. 30. 1927 2 Sheets-Sheet 2 Fig.2.

- lfllmmu lHlHlll lllll] mummy INVENTOR ATI'ORNEY Patented Sept. 17, 1929 UNITED STATES OFFICE RAY P. BIG-BEE, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELEC'JJRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA CONTROL SYSTEM- fir im tation filed September 3o, 192 7. .sriai waste.

invention relates to motor-control systems and it has particular relation to control systems for use with elevators, hoists and similar machinery.

' An object of my invention is to provide a control system for motors used with ma chinery designed to operate between a pluraflity of points of travel, wherein the motor may be automatically controlled to stop the machine accurately at such predetermined points.

Another object of my inventionis to provide a control system for elevators wherein the elevator may be automatically stopped accurately level with the several floors which it serves.

'A further object of my invention is to provide a control system for automatically stopping elevators accurately level with the floors, wherein the mechanism for achieving such accurate stoppingmay be located at a point remote from the floor.

Another object of my invention is to provide a control system for stopping elevators accurately with the floors which is readily adaptable for use with elevators having different numbers of accelerating speeds.

My invention will be described with reference to the accompanying drawings, wherein:

Figure 1 is a diagrammatic view of a control system for an elevator using my automatic stopping mechanism;

Fig. 2 is a plan view of the switch used to effect the automatic stopping. and

Fig. 3 is a view, in end elevation, of the switch illustrated in Fig. 2.

teferring to Fig. 1, the control system therein shown for a single elevator comprises an elevator car C suspended by a cable Ca, which passes over a hoisting drum D to a suitable counterweight (not shown) as is customary. The hoisting drum D is directly coupled to a hoisting motor EM, which is illustrated as of the shunt-wound type. The

' control for the motor EM is of the vari-volt MF, has its armature M directly coupled to the armature G of a generator G. The generatol; G ofthe variable-voltage compoundwound t 'pe, comprising an armature G, a

. series fie d winding GSF, a shunt field windihg GF and' a,,clemagnetizin field windin The armature G of t e enerator isconnected in l oo'p c'ireuitwit the armature EM of "the hoisting "motor ,EM. The motor EMis shown as having its field winding EMF connected directly across the supply lineslil and L2.

The elevator motor EM is. controlled, in theusual manner, through the agency of a car switch CS on the car, the usual control actuating devices"up-' and down direction switches designated 'as l and 2, respectively, and a 'series of speed switches 3, 4 and5. v

The, apparatus may bestbedescribed with reference to an assumed operation, Assuming 'the elevator to be at the first floor, the attendant on the car may start the car upwardly movement of the handle 10 of the switch CS to the left, thus completing a circuit for the up-direction switch 1 extending from line conductor L1, through conductors 11 and 12, normally closed contact members a of the,down-direction switch 2, conductor 13, the coil of up-direction switch 1, conductor 14, contact members 15, 16 and 17 of car switch CS and conductor 18 to line conductor L2.

The'up-direction switch 1 closes its contact membersb and 0, thus supplying the generator shunt field winding GF with current in 'one direction, by way of a circuit which extends from; line conductor L1, throughconductors 11 and 19, contact memhers I) on up direction switch 1, conductor 20, resistors 21, 22 and 23, conductor 24 generator shunt field winding GF, conductors 25 and 26, contact members 0 on up direction switch 1, and conductor 28 to line conductor L2. The generator thus supplies voltage in one direction to the elevator-motor armature EM, causing the elevator motor EM to move the car upwardly.

As the car switch CS is moved farther to the left, the contact member 16 is brought into co-operation with contact members 30,

31 and 32 to successively complete circuits to the actuating coils of speed relays 3, 4 and 5, which relays, in turn, successively short-circuit the resistors 23, 22 and 21 to increase the current supplied to the generator shunt field winding GF and to-ca'use the 'consequent acceleration of the elevator motor EM.

:The circuit for the speed relay 3 extends from; lineconductor L1, through conductors 11 and 19, to a contact brush 33 of a. slowdown and stopping switch S, (the construction and pur ose of whichis hereinafter described). T lience, the circuit "continues through a contact rin" 48, a contact brush 35, conductor 36, the oil of speed relay3, eonductor37, contact members 30, 16 and 17, of the car switch CS, and conductor 18 to line conductor L2. The circuits for the speed relays" 4 and 5 may be similarly traced through contact brushes 38 and 39, respectively, of two other contact rings on the slowdown switch S. g

"The slow-down switch S comprises a base '40 ig. 2) upon which is mounted a nor mally inactive shaft member 41 supported in suitable bearings 42 and 43. The bearings are secured to the base by attaching screws, such as shown at 4-4. Fixed near one 'end of the shaft 41 is agear-wheel 45 for drivin the shaft 41 A series of contact rings, designated'by the numerals 4G, 47, 48 and 49., respectively, are suitably supported u'pon' insulating discs 50, '51, 52 and 53, respectively, which are fixed to the shaft 41 in spaced 'relation. his may readily be seen by inspection of Figs. 1 and 2, the contact 49 extendssubstantially throughout a comp'lete circle, there being only a short arcuatc gap between the ends of the ring. he contact rings 48, 47 and 46 extend successively through lesser portions of a complete circle. 4 Each of the conta t rings has associated therewith a pair of contact brushes mounted upon opposite sides of the shaft 41, the brushes coacting with the contact ring 49 being designated by the characters 55 and 55', those for cooperation with the contact ring 48 being designated as 33 and 3!, those coacting with the contact ring 47 being designated as 38 and 38 and those cooperating with the. contact ring 46 being designated as 39 and 39'. The effect of the successively "shortened length of the contact members 49, 48, 47 and 46 is such that the rotation of the shaft 41, by movement of the gear-wheel 45, will cause the successive breaking of contacl between the brushes cooperating with the contact rings 46, 47, 48 and 49, in the order stated.

A shaft member 56 is suit-abl supported upon the base 40 by means of bearing memgers 57 and 58. and has fixed thereon a sprocket-wheel 59. A sleeve 60 keyed to the shaft :76 for rotation therewith but longitudinally movable with reference to the shaft 56, carries a suitable spur gear-wheel 61 for engagement with the gear-wheel 45 on the shaft. 41. A suitable helical spring 62, acting between the gear-wheel 61 and the face of a magnet coil 63, forces the s ur gearwhcel and the sleeve 60 to the eft upon the shaft 56, to normally maintain the gearwheels 45 and- 61 out of. engagement. The gearwvheels 61 and 45 thus constitute a clutch for coupling the shafts 41 and 56 for movement in correspondence with move ments of the elevator.

, The sleeve 60 is constructed of suitable magnetic material and constitutes the mavable core for a clutch-operatin solenoid, the energizing coil 63 for which is fixed ,to the base 40 by a suitable bracket 64. The sprocket-wheel 59 is 'suitablyconnected, in any well-known manner, to some part 'of the driving or operating mechanism for the ele-. vator. for example, as by a chain 65, to thus impart to the sproeket;wheel 59 a movement which .n'eorrespondence with the movements of the elevator up and down its shaft. Refer-rim" to F ig. 1, this chain 65 is rep E'csziliCxi as an endless chain which extends from a point of attachment to the elevator car. designated as 66, downwardly to a slrczivzrfii at the lowermost portion of the hatch\\'a i,-' and thence upwardly over the s irc-cicetn heel 59 and haul: 'to the point of attachment (56. In this n'xanne'r, the sprocketwheel 5.9 and the spur gear-wheel 61 will always move in correspondence with the ll'lO"-'Cllitl1i'$ of the elevator, regardless of stretching of the elevator cables or slippage between the cable and the hoisting drum D. The operation of thisslow-down switch S is such that the energization of the magnet coil (33 will draw the gear-wheel 61 into engagement with the gear-wheel 45, causing the motion of the elevator'car C to be transmitted to the several contact rings 46, etc., and thus causing movements of the contact rings to correspond to farther movement of the elevator car C. Vhen She coil 63 is deenergized, the. spring 62 will move the gear-wheels 45 and 61 out of engagement and permit a spring 68 to restore the shaft 41 and the contact rings to normal position. It should be noted that the same effect may be produced by having the spring 62 maintain the gear wheels in engagement and having the magnet 63 disengage them when the car is running at high speed.

Each of the up and down direction switches 1 and 2 and of the-speed relays 3, 4 and 5 is provided with a self-holding circuit that is closed by the actuation of the associated switch or relay. From an inspection of Fig. 1, it will-be seen that the holding circuits for the swit '-hes lead through the respective contact rings on the slow-down switch S. The holding circuit for the updirection switch 1 extends from line conductor L1, through conductors 11 and 12, contact member a on clown-direction switch 2, conductor 13, coil of Lip-direction switch 1,

conductors 14 and 70, cont-actmembers (i onup-direct-ionswitch 1, conductors 71 and 72-, brushes and 55 and the contact ring 49 of the slow-down switch S, and conductors 73 and 74 to line'conductor L2. The holding for the speed relay fiextcnds through the contact ring 46.

Assuming, for example, that-the elevator car C is to stop level with the second floor, represented by the :dotted line designated 2nd, the attendant upon the car will center the car switch CS some time prior to the arrival of the carat the second floor.

Through the operation of suitable inductor relays, designated as 75, for the up direction, and designated as-76 for the down direction, which relays may be of the type disclosed in the copending application of John F. Clancy, Serial No. 559,997, filed May 11.

1922, or in the copendingimplication of Harold V. Williams, Serial No. 190,482, filed May -11, 1927, (both applications being assigned to the \Vestinghouse Electric and Manufacturing Company), a circuit will be completed for energizing the magnet coil 63 of the slow-down switches when thecar is a predetermined distance away from the second floor level.

The circuit for the inductor relay '75 extends from line conductor L1, through eon ductors 11 and 19, contact members 7 on updirection switch 1, conductor 77, the coil of relay 75, conductors 78 and 7 9, contact members 80, 16 and 17, and conductor 18 to line conductor L2. Thus, as the inductor relay passes its cooperating magnetizable iron plate 81, suitably mounted in the hatehway, the relay will close its contact members 82 to complete the circuit for the clutch coil 63, which circuit extends from line conductor L1, through conductor 11, the. coil 63, conductors 83 and 84, contact members 82, and

. conductors and 18 to line conductor L2.

At this instaht, the energization of coil 63 will cause engagement of the gear-wheels 61 and 45, and further movement of the car C the'circuit to the speed-relay 5. Speed-relay 5 opens its contact members to re-insert the resistor 21 in circuit with the generator shunt field winding GF, thusslowing down the elevator motor EM. Further movement of the car 0 will, in like manner,deenergize the relays 4 and 3, successively, .to' reinsert the resistors 22 and :23 in circuit with the genera-- tor shunt field winding GF and cause furthe slowing downcfthe-m'otonEM. 1 After t-he.car :C has travelled a predetermined 'distance past-:t-heinductor plate 81, such distance beingsufii'cienbto bring the carlevel with the fioor,'. the ratio between the gear-wheels 61 and 45 is such that the shaft-41 will have moved through a sufficient distance to move the contact. ring 49 lout of' engagement with the contact brush 55', thus breaking the holding circuit forthe up directionswitch -1. -.'-'lhe consequentdeenergizationof the up-direction-switch '1 causes'the' ear to stop at such'time as it is' substantially level with the second floor.

By proper designing of the gear-wheels 61 and 45, and properly determining the length of the respective contact rings 46,"etc.',' the car may bemade to stop level with the; floor'with extreme accuracy. 4

It will be noted thatQw-ith my system, an

elevator car may have its movements com- 9 pletely controlled in an automatic manner without the necessity-of mechanica-l contact between the car and the hatchway, as is necessary in the-use'of cams and'rollers'and similar'devices. "Moreover,a large number of slow-down steps,"represented by the resisters 21, 22, etc, maybe incorporated'i'n an elevator control system using my slow down switch, by the-mere addition of a greater number of contact rings and discs on the slow-down switch shaft 41.

The use of the slow-down switch S, located remote from the elevator car C, also removes an objection to existing automatic controllingdevices for elevators in that there is no necessity for mounting'a large quantity of apparatus on the car structure. However, should it be desired to mount the switch S on the car, the only change required would be that of attaching the chain to the top and bottom of the shaft in place of the attachment to the car.

It has'not been deemed necessary to describe the operation of the relays and circuit when the elevator is travelling in the down direction, it being obvious that the operation is the same, with the exception that, in this instance, the contact rings 46, etc. are moved from engagementwith the contact brushes 39, 38; 33, and 55, the effective slow-down and stopping of the elevator being accomplished in the same manner as described for the up direction. a

While I have shown the final stopping of the elevator as controlled by the slow-down switch S, it is obvious that the final step may be accomplished by other-means; for example, by a second inductor-relay device similar to those designated and 76, or by a floor-selector device also actuated by the chain 65 as is described in Reissue Patent No. 17,097, to M. Baruch, dated October 9, 1928. Also the energization of the magnet 63 at the proper time may be accomplished in many ways other than by the inductorrelay device shown; for example, by contact members on a floor-selector, such as is commonly used for elevator signal. systems.

The embodiment of my. invention described is merely illustrative, and I do not desire to be limited to the details of the apparatus disclosed, except as defined in the appended,

travel, for actuating said controlling means to slow down and stop said elevator accurately at other.predetermined points in its travel. I

2. In a control system for elevators, motive means for said elevator, means for actuating said motive means to drive said elevator at a highspeed and a plurality of intermediate speeds, means for controlling said actuating means to slow down said elevator from high speed to stop in a series of successive steps of diminishing speed, andmeans driven in correspondence to move ments of said elevator engageable with said controlling means when said elevator arrives at predetermined points in its travel for actuating said controlling means to slow down and stop said elevator accurately at other predetermined points in its travel. a

3. In a control system for an elevator operable past a floor-niulti-speed motive means for said elevator, control means for starting and accelerating said elevator through successive steps of increasing speed, normally inactive means for actuating said control means to decelerate and stop said elevator, means operable in correspondence to movements of said elevator and means operably dependent upon the approach of said elevator to a predetermined distance from said floor for engaging said actuating means and said moveable means to slow down and stop said elevator level with said floor.

4. In a control system for elevators having a plurality of actuable devices for operating said elevator at different speeds, means for actuating said devices, means for maintaining said devices active when actuated, means for releasing said actuable device comprising a normally inactive member, a member movable in correspondence to movements of said elevator, and means for coupling said members for simultaneous movement when said elevator arrives at predetermined points in its travel.

5. In a control system for elevators, having a plurality of actuable devices for operating said elevator at difierent speeds, electroresponsive means for actuating said devices, self-holding means for maintaining said devices when actuated', means for releasing said actuable devices comprising a normally inactive member, a member movable in correspondence to movements of said elevator, and means for coupling said members for simultaneous movement when said elevator arrives at predetermined points in its travel.

6. In a control system for elevators, having a plurality of actuable devices for operating said elevator at different speeds, means for actuating said devices, means for maintaining said devices active when actuated, means for progressively releasing said actuable devices to slow down and stop said elevator in steps of progressively diminishing speed, said releasing means comprising a normally inactive member, amember movable in correspondence' to movements of said elevator, and means for coupling said members for simultaneous movement when said elevator arrives at predetermined points in its travel.

7. In a stop motion switch for elevators, a movable shaft, a plurality of contact members, means actuated by movement of said shaft for successively actuating said contact members, means movable in correspondence to movements of said elevator, means operable to couple said movable means and said shaft to move said shaft in correspondence to movements of said elevator from a normal position to an abnormal position, and means normally biasing said shaft to said normal position.

8. In a stop-motion switch for elevators, a shaft movable from a normal position to an abnormal position, means movable in correspondence to movements of said elevator, means operable to couple said movable means and said shaft to move said shaft in correspondence to movements of said elevator, a plurality of normally closed switching devices for controlling the movements of said elevator, and means on said shaft for successively-actuating said switches to open-circuit condition on movement of said shaft to abnormal position.

9. In a stop-motion switch for elevators, a shaft movable from a normal position to an abnormal position, means movable in correspondence with movements of said elevator, magnetic means operable to couple said movable means and said shaft to move said shaft in correspondence to movements of said elevator, a plurality of normally-closed switching devices for controlling the movements of said elevator, and means on said shaft for successively actuating said switches to opencircuit condition on movement of said shaft to abnormal position.

10. In a control system for elevators operable past a floor, motive means for said elevator, means for controlling the direction and speed of said elevator including an up-direction switch. a down-direction switch and a plurality of speed switches, means for actuating said speed switches and for selectively actuating either of said direction switches to cause said car to move at the highest speed, means for maintaining said switches closed when actuated, means movable from a normal position to an abnormal position for successively opening the active speed and direction switches to slow down and stop said elevator in steps of progressively diminished speed, and means operable when said car arrives at a predetermined distance from said floor for coupling said movable means to said elevator for movement in correspondence to the movements of said elevator to thereby stop said elevator accurately at said floor.

11. In a control system for elevators operable past a floor, motive means for said elevator, means for controlling the direction and speed of said elevator, including an up-direction switch. a down-direction switch and a plurality of speed switches, means for actuating said speed switches and for selectively actuating either of said direction switches to cause said car to move at the highest speed, means for maintaining said switches closed when actuated, means movable trom a normal position to an abnormal position for successively opening the active speed and direction switches to slow down and stop said elevator in steps of progressively diminished speed. means operable when said car arrives at a predetermined distance from said floor for coupling said movable means to said elevator for movement in correspondence to the movements of said elevator to thereby stop said elevator accurately at said floor. and means for returning said movable means to normal position.

In testimony whereof, I have hereunto subscribed my name this 19th day of Aug. 1927.

RAY P. HIGBEE. 

